I was on the 1962 to the Baltic. All the schools involved came from Hampshire. I have seen on the old Dunera web site that several people mentioned that there was a documentary made of the trip.
I have been trying for years to find this film and have finally tracked it down. It was made by the old Southern Television and was shown on Christmas day 1962 at 6:30 in the evening. After a lot of searching I have found a copy which is available from the Wessex Film and Sound Archive based at the Hampshire County Council Offices in Winchester. It cost me just £16 which was well worth the expense for the memories that it brought back.